On vagueness, 4D and diachronic universalism

I offer a new criticism of the argument from vagueness to four-dimensionalism [Sider 2001 Sider, Theodore. 2001. Four-Dimensionalism: An Ontology of Persistence and Time, Oxford: Clarendon Press. [Crossref] , [Google Scholar]. The argument is modelled after an older argument for mereological universalism [Lewis 1986 Lewis, David. 1986. On the Plurality of Worlds, Oxford: Blackwell.  [Google Scholar] and may be looked upon as a tightened-up and extended version of the latter. While I agree with other critics [Koslicki 2003 Koslicki, Kathrin. 2003. The Crooked Path from Vagueness to Four-Dimensionalism. Philosophical Studies, 114: 107–134. [Crossref], [Web of Science ®] , [Google Scholar]; Markosian 2004 Markosian, Ned. 2004. Two Arguments from Sider's Four-Dimensionalism. Philosophy and Phenomenological Research, 68: 665–673. [Crossref] , [Google Scholar] that the argument from vagueness fails precisely because of this affinity, my recipe for dealing with it is different. I reject the assumption, shared by Sider with his opponents, that synchronic composition and ‘minimal diachronic fusion’ are sufficiently similar to use considerations inspired by the analysis of the former to bear on the latter. My objection to a crucial premise of the argument from vagueness turns on the relevant aspect of dissimilarity between these two cases.     

Enduring and Perduring Objects in Minkowski Space-Time

I examine the issue of persistence over time in thecontext of the special theory of relativity (SR). Thefour-dimensional ontology of perduring objects isclearly favored by SR. But it is a different questionif and to what extent this ontology is required, andthe rival endurantist ontology ruled out, by thistheory. In addressing this question, I take theessential idea of endurantism, that objects are whollypresent at single moments of time, and argue that itcommits one to unacceptable conclusions regardingcoexistence, in the context of SR. I then propose anddiscuss a plausible account of coexistence forperduring objects, which is free of these defects. This leaves the endurantist room for some maneuvers. I consider them and show that they do not really helpthe endurantist out. She can accommodate the notionof coexistence in the relativistic framework only atthe cost of renouncing central endurantist intuitions.     

Defining ‚exdurance’

On stage theory, ordinary continuants are instantaneous stages which persist by exduring—by bearing temporal counterpart relations to other such stages. Exduring objects lack temporal extension and there is a sense in which they are wholly present at multiple instants. How then is exdurance different from endurance? I offer a definition of ?exdurance’ that clearly sets it apart from other modes of persistence.     

Zero-Value Physical Quantities

Synthese - To state an important fact about the photon, physicists use such expressions as (1) “the photon has zero (null, vanishing) mass” and (2) “the photon is (a) massless...